`/// <reference lib` is stripped out of `d.ts` file

[SimenB]

🔎 Search Terms

reference lib elided disposable

🕗 Version & Regression Information

• This changed between versions 5.4.5 and 5.5.2

(not fixed in nightly)

⏯ Playground Link

https://www.typescriptlang.org/play/?ts=5.5.2#code/PQgEB4CcFMDNpgOwMbVAGwJYCMC8AiaAZ0WgA8AXAOgBNMiAHAeyIENt1p9RgA+AKH7lmkCqEyIKCWK1SgAKgAsJAc1DkpiGkVAAReszYc0AbwC+QA

💻 Code

/// <reference lib="esnext.disposable" />

export interface Thing extends Disposable {}

🙁 Actual behavior

Output d.ts is

export interface Thing extends Disposable {
}

🙂 Expected behavior

The .d.ts file should be like it was in 5.4.5

/// <reference lib="esnext.disposable" />
export interface Thing extends Disposable {
}

Additional information about the issue

No response

[jakebailey]

This is by design: https://devblogs.microsoft.com/typescript/announcing-typescript-5-5/#simplified-reference-directive-declaration-emit

Changed in #57681.

You must now write:

/// <reference lib="esnext.disposable" preserve="true" />

[SimenB]

Ah, somehow missed that. Thanks!

An awesome change - I have some code when building definition files I can probably delete, then.

https://github.com/jestjs/jest/blob/046787eafae9ea0515b19e81f30758e0f040f077/scripts/buildTs.mjs#L205-L232